Reciprocating engines are often relied upon to provide increased power density, reduced fuel consumption and emissions, and increased reliability and uptime. Multi-cylinder engine arrangements are required to increase modularity and power levels, leading to twenty or more cylinders in a “V” formation. Such a configuration leads to particularly long crankshafts that are more flexible in torsion. All of the above trends are creating severe crankshaft torsional vibration challenges.
As an example, U.S. Pat. No. 8,807,108 describes a pendular dampener arranged to counterweight journal pins formed along a crankshaft and configured to couple with connecting rods. The configuration of the pendular dampeners may attenuate vibrations in the crankshaft caused by the associated journal pins. The pendular dampeners may also increase the stiffness of the crankshaft reducing bending in the crankshaft, thereby increasing the efficiency of the crankshaft during rotation and reducing vibration. The pendular dampeners also provide additional unloading of main bearing inertia forces. However, the pendular dampeners of U.S. Pat. No. 8,807,108 do not address torsion forces in the crankshaft due to resonance of the crankshaft. The disclosure addresses these and other shortcomings of the prior art.